1. Field of the Invention
The present invention relates generally to vehicle washing facilities and, in particular, the present invention relates to a blower assembly to dry vehicles cleaned in washing facilities.
2. Background of the Invention
Washing assemblies to automatically wash and dry vehicles normally provide a series of wetting, washing, and rinsing cycles. At the conclusion of these cleaning cycles, drying equipment is frequently included to remove moisture from the surface of the cleaned vehicle.
The washing facility owner has an incentive in drying each automobile as quickly as possible to move the maximum number of vehicles per unit of time through the car wash. For customer satisfaction and return business the car must be dried in minimum time. Thus, a drying system that is fast and efficient is extremely important.
Washing facility operators have found that a highly focused and oscillating blast of air is highly efficient for removing water remaining on vehicle surfaces after washing cycles. Attempts have been made to focus air discharges by putting blower outlet nozzles close to the surface of the vehicle. Presently there are many designs which focus and oscillate air discharges for vehicle washing facilities. Moreover, similar designs are present for other applications, such as those which direct focused and oscillating (or rotating) air discharges toward textile equipment. The most relevant of these designs known to the Applicants are discussed hereinbelow.
U.S. Pat. No. 4,161,801, issued to Day et al. Jul. 24, 1979, discloses a fluid stripping apparatus. The apparatus includes a flexible, inflatable bag with a generally rectangular transverse cross-section. The inflatable bag includes an inlet and an elongated opening. The inlet is present to admit pressurized air into the bag. The elongated opening is present at one end of the bag and defines a nozzle and an air distributor. The nozzle emits a stream of air from the bag onto the vehicle. The air distributor supplies the air to the bag and supports the bag so that the bag extends toward the object being dried. The nozzle end of the bag lies in the path of motion of the vehicle, thereby causing physical engagement between the nozzle end of the bag and the vehicle to bring the stream of air emitted from the nozzle into close spatial relationship with the surface of the vehicle. This can cause problems such as causing potential damage to the vehicle surface by contact of the blower output nozzle.
U.S. Pat. No. 4,393,602, issued to Smith Jul. 19, 1983, discloses a vehicle drying machine and method. The vehicle drying machine includes a set of round nozzles. All nozzles are supplied with pressurized air from a plenum to dry the sides and top of a motor vehicle departing the washing apparatus. Each nozzle is employed at an angle and is oscillated for thorough coverage. Preferably the nozzles are slender and cone-shaped so that the air blast remains concentrated at a high velocity for a significant distance away from the nozzle outlet. One disadvantage is that air hoses are required to convey pressurized air from a source to the nozzles. Another disadvantage is that an extensive linkage apparatus is necessary to oscillate the nozzles.
U.S. Pat. No. 4,587,688, issued to Gougoulas May 13, 1986, discloses a proximity detector system for automatic car washer/dryer equipment. The system includes an apparatus for maintaining close proximity between a vehicle surface and a forced air water stripper, without contacting the vehicle surface. Air is supplied to a plenum box from a blower/turbine via a trunk tube. The air is conveyed from the plenum box via a tube to a plurality of nozzles. Each nozzle is preferably provided with small plastic wheels. The wheels are operative only during that portion of the drying cycle when the windshield and backlight of the vehicle are proximate to the nozzle and function to prevent the nozzle from directly contacting, and potentially damaging, the vehicle. However, contact with the vehicle in this manner can nonetheless create the perception of potential damage to the vehicle. An ideal drying system will provide a focused blast of air with the blower nozzle sufficiently separated from the vehicle to eliminate any perception of risk of damage by contact with the vehicle.
U.S. Pat. No. 4,685,169, issued to Nelson Aug. 11, 1987, discloses a vehicle washer and dryer. The apparatus includes a track gantry that moves along a track and over a vehicle being washed. Water outlets and brushes are present on the gantry to wash the car. The apparatus further includes a blower with a nozzle and an oscillator. A flexible coupling connects the nozzle to the fixed blower housing. The nozzle directs air expelled from the blower onto the vehicle. The oscillator periodically changes the orientation of the nozzle and thus alters the direction of the air expelled from the nozzle. One disadvantage is the necessity of an extensive linkage system to oscillate every nozzle. Another disadvantage is that the flexible couplings will need to be replaced if they become brittle due to exposure to light, water, and detergent.
U.S. Pat. No. 5,367,739, the entire disclosure of which is hereby incorporated by reference, issued to Johnson Nov. 29, 1994, discloses oscillating air blowers for drying vehicles. Prior art FIG. 6 illustrates the Johnson configuration. A vehicle drying blower assembly disclosed therein includes a series of oscillating fan housings, each with a discharge nozzle. A centrifugal fan is disposed in each fan housing. Each fan is powered by a blower motor and rotated by a drive shaft. The blower motor is stationary with respect to the fan housing. The fan housing is supported by a rocker arm to pivot the fan housing coaxially with the circular fan drive shaft. The rocker arm further pivots about a bearing assembly which is also coaxial to the drive shaft of the blower motor. A drive motor rotates an eccentric crank arm. Link rods coupled between the eccentric crank arm and the rocker arms simultaneously oscillate each fan housing. Thus, a rather complex, bulky cantilevered rocker arm-link rod assembly is necessary to oscillate the fan housing with respect to the stationary motor. The cantilevered design makes the overall fan housing structure susceptible to damages and misalignment which can present a significant hazard considering the high rate of rotation of such blower motors and fans.
U.S. Pat. No. 3,525,117, issued to Gleaton Aug. 25, 1970, discloses an apparatus for cleaning textile looms. Said patent is incorporated herein by reference. The apparatus includes an overhead crane, a carriage, blower units, means for indexing the carriage on the crane, and means for rotating the blower units. Each blower unit includes a motor disposed between a pair of centrifugal blowers. A single motor shaft extending from the motor rotates both blower fans. Oscillating fan housings are connected to the stationary motors to vary the direction of air streams from the fan housings. A bearing is disposed generally around the motor drive shaft and is used to connect the motor to each fan housing. An inner race of the bearing is fixed to the motor and an outer race of the bearing is connected to the fan housing. The structural support of the fan housing is quite limited and is almost exclusively provided through said bearings. Thus, the assembly may be quite susceptible to damage or misalignment. An oscillating motor is secured to the underside of a plate. An output shaft of the oscillating motor turns a belt which rotates a crank. The crank in turn, rotates a pair of rods. The remote ends of the rods are pinned to the blower crank arms. Actuating the oscillating motor reciprocates the push rods to oscillate the fan housings through limited angular distances. Thus, to provide an oscillating air flow, the fan housing and fan motor are coupled by a bearing which must support the entire weight of the fan housing. Moreover, because the motor is stationary, an extensive linkage system must be present to oscillate the fan housing. Prior art FIG. 5 illustrates the Gleaton configuration.
U.S. Pat. No. 2,976,557, issued to King Mar. 28, 1961, discloses a traveling cleaner for textile machinery. The traveling cleaner includes one or more motors attached to brackets. Each motor includes a horizontal drive shaft extending from each end of the motor casing. A fan is secured to each end of the drive shaft. Blower casing elements surround their respective fans. Each of the blower casing elements has an axial air intake and at least a single, and preferably a pair of, tangential oppositely directed outlet nozzles disposed 180.degree. apart about the axis of the blower. The nozzles direct air streams in opposite directions in a vertical plane. A horizontal shaft is arranged parallel with each motor shaft and extends through the bracket structure on which the motor is mounted. Sprockets are mounted on opposite ends of each shaft and a chain connects each sprocket with a larger companion sprocket in alignment therewith to oscillate or rotate the blower casing. Hence, an extensive additional support frame is necessary to oscillate or rotate the casing with respect to the stationary motor.
There is then a need for a simplified, yet effective and durable, linkage between an oscillating or rotating fan housing and a fan motor and the support frame. There is a particular need for a system which generates an oscillating or rotating air flow, which has an efficient air flow design, and is more robust than known configurations. In one such robust system, the fan housing and fan motor would be held in a substantially rigid relationship and oscillated as a unit.